Adding a new circuit to an exsisting Consumer-unit

Adding a New Circuit to Your Consumer Unit — Part P & What's Required

By LC Fisher Electrical Services — Your Local NICEIC Registered Electrician, Nottingham

📌 Is Adding a New Circuit "Notifiable Work"?

Short answer: YES. Installing a completely new circuit back to your consumer unit is classed as notifiable work under Part P of the Building Regulations. That means it must be properly certified — it's not something you can just do and forget about.

📋 What Exactly Needs to Happen

Here's a clear breakdown of the full process — from start to finish 👇

🛠️ PHASE 1 — Design & Installation

Before any cables go in, the electrician must:

✅ Design the circuit correctly — calculate cable size, protective device rating, and installation method in accordance with BS 7671 (IET Wiring Regulations)

✅ Check the consumer unit has capacity — physically and electrically — for the new circuit

✅ Install the wiring safely — correct cable type, properly secured, protected from damage

✅ Ensure earthing & bonding is adequate — the new circuit must have a reliable earth path

✅ Fit appropriate protection — usually an RCBO for individual circuit protection, plus SPD where required

🔍 PHASE 2 — Inspection & Testing (Critical Step!)

Before the power goes on, the work must be thoroughly inspected and tested:

Required Test What It Checks

✅ Continuity of protective conductors Your earth wire is continuous throughout

✅ Insulation resistance No damage or leakage in the cable

✅ Polarity Line and Neutral connected the right way round

✅ Earth fault loop impedance The protection will trip fast if there's a fault

✅ RCD/RCBO operation Tests that it actually trips when it should

✅ Visual inspection Everything installed neatly and safely

📝 This isn't optional. Every new circuit must be inspected and tested before being energised. If cables get covered before inspection, it becomes much harder — and more expensive — to check later.

📄 PHASE 3 — Certification

On completion, the electrician MUST issue:

• ✅ Electrical Installation Certificate (EIC) — not a "minor works" certificate, this is a full certificate for new circuits

• ✅ Schedule of Inspections — confirming visual checks completed

• ✅ Schedule of Test Results — actual readings from all tests carried out

• ✅ A copy for you, a copy for their records, and one for Building Control (via the notification route)

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🏗️ PHASE 4 — Building Control Notification

There are only two legal ways to handle this — and one is much easier than the other 👇

✅ OPTION A — Use a NICEIC Registered Electrician (The Smart Route!)

Because NICEIC is a government-approved Competent Person Scheme, we can self-certify the work:

• ✅ We notify Building Control electronically on your behalf

• ✅ No forms for you to fill in

• ✅ No separate council inspection fees

• ✅ You receive a Building Regulations Compliance Certificate automatically from NICEIC within around 30 days

• ✅ Fast, simple, and fully compliant

⚠️ OPTION B — Building Notice Application (If NOT using a registered electrician)

If you use someone who is not NICEIC registered — or do it yourself — you MUST do the following BEFORE work starts :

• ❌ Submit a Building Notice application to your local council's Building Control department

• ❌ Pay the required fee (typically £150–£300)

• ❌ Arrange inspections: before cables are covered up AND on completion

• ❌ Have the work independently tested and certified by a competent person

• ❌ Obtain the EIC and submit a copy to Building Control yourself

❗ Important: Failure to notify notifiable work is a breach of Building Regulations. It can cause major problems when selling your home, invalidate insurance, and local authorities can insist work is removed or brought up to standard at your own cost.

📊 Quick Summary — Who Does What?

Step What Needs Doing Who Does It?

📐 Design Circuit designed & sized correctly Electrician

🔧 Install Cables, accessories, connection to consumer unit Electrician

🔍 Test Full inspection + all required tests Electrician

📄 Certify Issue EIC + test schedules Electrician

🏛️ Notify Tell Building Control ✅ NICEIC electrician does this automatically.

 ⚠️ Unregistered = YOU must apply to council BEFORE starting

💡 Common Questions

❔ Can I just add a new circuit myself?

Technically yes — but only if you submit a Building Notice application to your local council before you start, pay their fee, have the work inspected and tested, and obtain full certification. Most people find it cheaper and far simpler to use a NICEIC electrician.

❔ What if I don't get it certified?

You won't have proof the work meets regulations. Solicitors will ask for certificates when you sell your home — missing paperwork can delay or kill a sale. In an insurance claim, uncertified electrical work could invalidate your policy.

❔ Is adding a spur to an existing circuit the same thing?

No — that's not notifiable work, though it still needs to be safe and ideally issued a Minor Works Certificate. A completely new circuit running back to the consumer unit = notifiable work.

🛡️ We Handle Every Step for You

At LC Fisher Electrical Services, adding a new circuit means:

• ✅ Proper design & installation to BS 7671 standards

• ✅ Full inspection & testing — we document every reading

• ✅ Electrical Installation Certificate issued on completion

• ✅ Automatic Building Control notification via NICEIC — nothing for you to do

• ✅ Building Regulations Compliance Certificate sent directly to you

• ✅ Fully insured, fully qualified — peace of mind built in

📞 Need a new circuit adding? No job is too small. Call us on 07891 993003 or message us — we'll come and quote, handle all the paperwork, and leave you with everything fully certified and compliant.